What do parentheses in a Perl regex do?

Posted by iamrohitbanga on Stack Overflow See other posts from Stack Overflow or by iamrohitbanga
Published on 2010-03-13T05:24:38Z Indexed on 2010/03/17 3:11 UTC
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perl

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regex

I have been trying several regular expressions in the substitution operator:

$str =~ s/^0+(.)/$1/;

converts 0000 to 0 and 0001 to 1

$str =~ s/^0+./$1/;

converts 0000 to empty string, 000100 to 00, 0001100 to 100.

what difference is the parentheses making?

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